Hi, Jingsong. Thanks for your feedback. > Does this need to be a function call? Do you have some example? I think it'll be useful to support function call when user call procedure. The following example is from iceberg:[1] CALL catalog_name.system.migrate('spark_catalog.db.sample', map('foo', 'bar'));
It allows user to use `map('foo', 'bar')` to pass a map data to procedure. Another case that I can imagine may be rollback a table to the snapshot of one week ago. Then, with function call, user may call `rollback(table_name, now() - INTERVAL '7' DAY)` to acheive such purpose. Although it can be function call, the eventual parameter got by the procedure will always be the literal evaluated. > Procedure looks like a TableFunction, do you consider using Collector something like TableFunction? (Supports large amount of data) Yes, I had considered it. But returns T[] is for simpility, First, regarding how to return the calling result of a procedure, it looks more intuitive to me to use the return result of the `call` method instead of by calling something like collector#collect. Introduce a collector will increase necessary complexity. Second, regarding supporting large amount of data, acoording my investagtion, I haven't seen the requirement that supports returning large amount of data. Iceberg also return an array.[2] If you do think we should support large amount of data, I think we can change to return type from T[] to Iterable<T> [1]: https://iceberg.apache.org/docs/latest/spark-procedures/#migrate [2]: https://github.com/apache/iceberg/blob/601c5af9b6abded79dabeba177331310d5487f43/spark/v3.2/spark/src/main/java/org/apache/spark/sql/connector/iceberg/catalog/Procedure.java#L44 Best regards, Yuxia ----- 原始邮件 ----- 发件人: "Jingsong Li" <jingsongl...@gmail.com> 收件人: "dev" <dev@flink.apache.org> 发送时间: 星期一, 2023年 5 月 29日 下午 2:42:04 主题: Re: [DISCUSS] FLIP-311: Support Call Stored Procedure Thanks Yuxia for the proposal. > CALL [catalog_name.][database_name.]procedure_name ([ expression [, > expression]* ] ) The expression can be a function call. Does this need to be a function call? Do you have some example? > Procedure returns T[] Procedure looks like a TableFunction, do you consider using Collector something like TableFunction? (Supports large amount of data) Best, Jingsong On Mon, May 29, 2023 at 2:33 PM yuxia <luoyu...@alumni.sjtu.edu.cn> wrote: > > Hi, everyone. > > I’d like to start a discussion about FLIP-311: Support Call Stored Procedure > [1] > > Stored procedure provides a convenient way to encapsulate complex logic to > perform data manipulation or administrative tasks in external storage > systems. It's widely used in traditional databases and popular compute > engines like Trino for it's convenience. Therefore, we propose adding support > for call stored procedure in Flink to enable better integration with external > storage systems. > > With this FLIP, Flink will allow connector developers to develop their own > built-in stored procedures, and then enables users to call these predefiend > stored procedures. > > Looking forward to your feedbacks. > > [1]: > https://cwiki.apache.org/confluence/display/FLINK/FLIP-311%3A+Support+Call+Stored+Procedure > > Best regards, > Yuxia